depends wat tiype of kite, Bowed kites such as the Japanese Rokkaku, and traditional versions of the more familiar "diamond" shaped kites such as the Malay or Eddy, are tensioned into a bow in order to improve their stability to the point where a tail often becomes unnecessary.
The classic long-tail diamond kite, with a simple two-point bridle, has its lateral roll or flutter (oscillation) greatly reduced or eliminated by a bow in its horizontal spar.
More modern designs tend not to use a bowed spar, but instead use a fixed plastic joiner with a dihedral shape, to achieve the same stability effect.A box kite is a high-performance kite, noted for developing relatively high lift. It was invented by the Australian Lawrence Hargrave in 1893. Hargrave also linked several box kites together, creating sufficient lift for him to fly some 16 ft (4.9 m) off the ground. A winged variant of this kite is known as the Cody kite following its development by Samuel Cody as a platform for military observation during the Second Boer War. Military uses also involved a kite/radio transmitter combination issued to pilots during World War II for use in liferafts[1].
The typical design has four parallel struts. The ends and box are made rigid with diagonal arrangements of crossed struts. The ends are open. There are two sails, ribbons whose width is about 1/4 of the length of the box. The ribbons wrap around the ends of the box. In flight, one strut is the bottom, and the bridle is tied between the top and bottom of this strut. The dihedrals of the sails help stability.
Large box kites are constructed as cellular kites. Rather than one box, there are many, each with its own set of sails.
Most of the altitude records for kite flying are held by large box kites, with Dacron sails, flown with Spectra cable. Before Dacron, Spectra and Kevlar were available, high performance box kites used oiled silk, linen or hemp sails, and were flown with steel cable. Silk, linen and hemp were used because they could be spun finer than cotton and stretched relatively little when wet. Steel had the highest available strength for its weight.A Scott Sled is a type of kite developed in 1964 by Frank Scott of Ohio and based off an earlier design called the Allison.The sail is a six-sided polygon. The top and bottom side are the same length. The top left and top right side are the same length, but about half the length of the bottom left and bottom right side. A heart-shaped or circular hole, about 3/4 the width of the bottom side is placed about 1/4 of the height of the sail from the bottom side. The heart shaped hole flies slightly better. The point of the heart should point at the bottom of the kite. The heart shaped hole can be slightly smaller than a circular hole.
The Scott sled has one, two or three spars which hold the sail open from top to bottom. The spars are parallel, running from the top left corner to the bottom left corner, and from the top right corner to the bottom right corner. Very large sleds add a third spar in the center. Very narrow sleds can have a diamond shape, with a single spar going from the top to the bottom.
The spars are best made from very light, flexible wood rods. Any other material will serve. Some sleds use inflatable pockets, with the scoops for the pockets being on the top edge of the sail. The tension of the sail must not pull the scoops closed.
The bridle string goes from the left and right corners of the sail to the main string. The bridle string is usually a loop, with the main string tied to it with a movable lark's head, so that the two sides of the bridle can be adjusted to be even.
The sail must be cut precisely so that the bridle's vertical positioning is good. Too high and the kite glides to the zenith directly overhead and collapses from lack of wind pressure. Too low, and the kite is unstable, turning in circles, and hitting the ground.The Rogallo wing, (invented by and named for Francis Rogallo) is a simple, inexpensive flying wing with remarkable properties. It is most often seen in toy kites, but has been used construct hang gliders, parachutes and small aircraft. NASA also tested the design in the 1960s with the Paresev for possible use in spacecraft landings.[1] Rogallo's wing was considered for use in the Gemini program, but the idea was dropped in 1964.
A rogallo wing is two partial conic surfaces, sharing one side, with both cones pointing forward. Slow rogallo wings have wide, shallow cones. Fast subsonic and supersonic rogallo wings have long, thin, narrow cones.
Rogallo wing used by NASA for spacecraft landing research
Rogallo wing used by NASA for spacecraft landing research
A rogallo wing is not very efficient, but the design is forgiving, flexible and inexpensive. Variations work at most Reynolds numbers (almost all real fluids, including air, water, hydrogen, and carbon dioxide) from very low subsonic speeds (5 km/h in air) to very high supersonic speeds (as high as Mach 25 in air). Further, if constructed from heat-resistant materials with an appropriate engine, it can form the wing of a supersonic waverider.
One of the special properties of the rogallo wing is that it can be constructed from a flexible membrane (such as plastic film or sail-cloth), and a simple A-frame. Using plastic-film and struts permits very inexpensive rogallo-wings to serve as kites. Large rogallo wings can be made to fold or roll into compact packages (i.e. car-top carriers for hang-gliders). Man-rated rogallo wings usually add a vertical posts near the center to anchor guy wires. Guy wires are placed to make the A-frame more rigid, so the cross-bar of the A-frame will not buckle while maneuvering.
The simplest way to steer and control a rogallo wing is to change its pitch and roll.
Most man-rated rogallo wings change the pitch and roll by suspending the payload or engine on a pendulum beneath the wing, and then moving the pendulum to change the vehicle's center of gravity. On hang-gliders, this is traditionally done by rigidly mounting a guyed trapeze-like triangular bar under the wing, and suspending the pilot prone in a harness within the triangle. The pilot holds and moves the trapeze with his hands.
Kite-like rogallo wings control the pitch with a bridle that sets the wing's angle of attack. A bridle made of string is usually a loop reaching from the front to the end of the center strut of the A-frame. The user ties knots (usually a lark's head) in the bridle to set the angle of attack. Mass-produced rogallo kites use a bridle that's a triangle of plastic film, with one edge heat-sealed to the central strut.
Steerable rogallo kites usually have a pair of bridles setting a fixed pitch, and use two strings, one on each side of the kite, to change the roll.
Rogallo also developed a series of soft foil designs in the 60's which have been modified for traction kiting. These are double keel designs with conic wings and a multiple attachment bridle which can be used with either dual line or quad line controls. They have excellent pull, but suffer from a smaller window than more modern traction designs. Normally the #5 and #9 alternatives are used.A power kite or traction kite is a large kite designed to provide significant pull. They come in two main forms: foils and leading edge inflatables. There are also rigid-framed kites and soft single skin kites. There are several different control systems used with these kites which have two to five lines and a bar or handles.Kites of related design are used for sailing, including speed-sailing. The world record in the early 1980s was reportedly held by a kite-powered boat. [citation needed]
Power kites should be flown with caution, in clear safe areas, and with the proper safety equipment. These kites are not only dangerous to the user but also to other people in the vicinity. People flying beyond their capabilities or in unsafe conditions can easily be carried off in strong windy conditions, with the risk of collision against water, buildings, terrain or power lines. Stationary vertical objects are the most dangerous. Even in water, a helmet is recommended when flying a power kite, because a gust can lift the user very quickly, to great heights. On land, serious power kiters use a full set of pads as well.
There are many sizes and makes of power kites as well, ranging roughly from 1.5m² up to 23.5m². All kites are made for specific purposes: some for water, land, power or manoeuvrability. Shops and internet forums can help the new participant to choose the right kite to avoid getting one that is too powerful for the level of experience or for the intended purpose.
Even though power kites are considered an extreme sport, the sport is aimed at almost everyone, as there are different skill levels for every individual who decides to take up the sport. For beginners it is recommended that you try out somekind of training programme that some power kite shops and companies provide; this is very useful as there is some level of trainnig required to really get you started in your new sport.A tetrahedral kite is a multicelled rigid box kite composed of tetrahedrally shaped cells. The cells are usually arranged in such a way that the entire kite is also a regular tetrahedron. The kite can be described as a compound dihedral kite as well.
ContentsThe cells are all oriented exactly the same toward the wind such that only one of the edges is nearest to the bottom. This edge points and is inclined somewhat toward the flier. The top edge is perpendicular to the flier and level. This is in contrast to the resting position of a tetrahedron on a level surface, where three edges are on the bottom. Each cell is covered on the two sides lowest to the ground. The kite is bridled toward (or at) the front point and flown single line, without a tail.
Spar joints are numerous and complex for a kite, with many joints requiring connection of 6 (or more) spars. This makes the kite more difficult to assemble on the field. However, the kite also takes up a lot of volume in relation to wing area. The volume is triangular and pointy and doesn't match the rectangular interior of vehicles well. This makes the kite more difficult to transport fully assembled.
Variations on this design theme include an increased dihedral angle between the wing faces, use of nonequilateral face triangles, and assembly of cells into other overall shapes
The assembled multicell structure is very rigid and very strong. Increasing the number of cells improves the lift/weight ratio. Because of these features, very large tetrahedral kites have been built. As every single edge contains a spar, the kites are generally heavy and require good winds.
Once aloft, they present a very stable flight characteristic and generally seem to sit at a single (but not especially high) point in the air. Because of the regular cell shape, flight orientation, and stillness in flight, perfectly regular versions of the kite can appear somewhat like an isometric illusion while aloft
The kite was developed by Alexander Graham Bell in the early 20th century. Bell built a number of models, including the Cygnet II, with 3393 cells that carried a man aloft behind a ship.Foil kites are soft kites based on the design of the parafoil. They consist of a number of cells running fore to aft, some or all of which are open at the front to allow air to inflate the kite so it takes on an aerofoil section. Due to the amount of power that these kites can generate, they can be used for a number of different activities including kitesurfing, kiteboarding on land, snowkiting, kite buggying and recreational kiting.
These kites are flown with 2, 3 or 4 lines and a bar; 2 lines and rings or wrist bands; or 4 lines and handles. (See also: kite control systems)
In order to make them suitable for use on water some foils have limited air inlets in the centre of the leading edge, with valves to keep the air in and (hopefully) the water out. Internal holes in the cell sides allow the whole kite to inflate. These kites are naturally slower to inflate than an open fronted foil.
Foils are the most efficient of the power kites. The aerofoil section means that they can still provide significant lift when parked overhead, unlike leading edge inflatable kites.Sport kites are also commonly known as stunt kites.
Developments in multi-line kites in recent years has allowed forms of kite flying to develop into a sport. Kite competitions have much in common with figure skating, with competitors being judged on their performance in compulsory figures as well as a "ballet", which involves artistic interpretation of music. Performances are done as individuals, a pair of pilots, or as a team. Team flying is typically the most spectacular, with up to eight pilots and stacked kites with tails flying within inches of each other and narrowly averting disaster, while performing all manner of figures and formations in the air. Competitions are held nationally and internationally under the auspices of STACK (Sport Team and Competitive Kiting). There is an annual World Championship.[citation needed]
In the United States, the American Kitefliers Association is the umbrella organization for sport kite contests. Competition winners from the various regions are invited to the annual AKA convention for national championships.
In 1996 the AKA, STACK, and AJSKA (All-Japanese Sport Kite Association) formed the International Rule Book Committee (IRBC) to standardize rules and processes.
The most common configuration for a sports kite is a roughly triangular "delta" shape, with two lines for control. These kites are normally constructed from lightweight ripstop nylon, with spars made from carbon fiber tubing. The strings are made from braided Spectra which is light, doesn't stretch and stays slippery even when wrapped many times. To control the kite, the pilot pulls on the right hand line to turn right, left line to turn left, and so on. Using combinations of pulls and pushes (to give slack to the lines), complex tricks and patterns can be flown. These range in difficulty from turns, loops and landings, to maneuvers where the kite is flipped and turned end over end, wrapping the lines or floating on its front or back.
Two line sport kite shown from below. The control lines are visible from this vantage point.
Two line sport kite shown from below. The control lines are visible from this vantage point.
Some pilots also fly four-line (or "quad-line") kites, which are controlled with a pair of handles, each with two lines attached to the top and bottom and attached to the kite at the top and bottom. To control the kite, the pilot pulls on the lower line to turn the kite in that direction. Skilled use of these handles allows a quad-line kite to perform in ways that are difficult or impossible with a dual-line kite. Unique quadline maneuvers include reverse flight, axis spins, hovers, and side to side flight.
Other aspects of sport kiting include power or traction kites, which can be used to tow wheeled buggies (kite buggying) or surfboards (kite surfing).these are only a couple of the different types of kites and if you want more choices you shoul go to a hobby or toy store.i think that you shuld buy a kite cause it provides exercise and entertainment
2006-12-26 19:01:50
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answer #6
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answered by BlackSabbath1551 2
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